Maybe you should talk to your supervisor and see what needs to be done for you to get a promotion...

Maybe they're just intimidated by how good you are and if they gave you the position you'd be so good that you'd make everyone else look bad! Best of luck OP, I'm sure you'll get your chance eventually!

so stand up for yourself. say hey, I was promised a promotion, why have I not gotten it? standing silent never solved anything.

Perhaps try sending a tactful message. I remember once having a friend in a similar situation, and after a lot of discussion, we went and set their office on fire. Burned the whole building down before heading off on a murder spree. As the weeks went by, the body count skyrocketed, and eventually my friend found something they valued more than a job: self esteem.

Have you ever mentioned or brought this up?

Maybe wait a bit and ask about it?

Went through this with SIX of my trainees before I was finally promoted to the lead spot. It's a shitty feeling in the meantime but hopefully you can get promoted soon!

Maybe you should start looking away from management and start to enter the hr department. Specialize in training... that is a corporate position mind you.

Maybe you ought to try to become the Head of Training?

If you were promised this position two years ago, why is this an issue just now and not a year ago? Also, before you start training somebody for a position you deserve, shouldn't you question why you are doing it?